Use of Time- and Frequency-Domain Approaches for Damage Detection in Civil Engineering Structures

Table 5

The shift of the first eigenfrequency (Hz) from the intact state until before the collapse (always unloaded state).

	RC slab					PrC slab
State	#0	#0*	#1*	#2*	#3*	#0	#0*	#1*	#2*	#3*
𝑓 by peak picking	11	9.18	8.07	7.85	7.69	11.75	11.70	11.65	11.65	11.55
𝑓 by SSI	11	9.20	8.00	7.70	7.60	11.73	11.65	11.61	11.56	11.33